SCN5A Variant c.2436+12G>A Detail

We estimate the penetrance of LQTS for SCN5A c.2436+12G>A around 47% and the Brugada syndrome penetrance around 16%. SCN5A c.2436+12G>A was found in a total of 1 carriers in 1 papers and/or in gnomAD: 0 had Brugada syndrome, 1 had LQTS. c.2436+12G>A is not present in gnomAD. c.2436+12G>A has been functionally characterized in 1 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (1 diagnosed with Brugada syndrome) and 5 individuals for LQTS (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A c.2436+12G>A around 47% (2/11) and the Brugada syndrome penetrance around 16% (1/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 18 48
PROVEAN scores less than -2 are considered deleterious. REVEL scores higher than 0.5 or 0.75 are considered likely pathogenic (higher sensitivity with the former cutoff, higher specificity with the latter cutoff). A PolyPhen-2 score of 0.85 or greater is considered likely pathogenic. BLAST-PSSM reflects the evolutionary conservation of residue substitutions, more negative numbers indicate fewer observations of the specific substitution than is expected. Penetrance Density is our previously published method to calculate the average BrS/LQTS probability density in a shell of residues surrounding a residue of interest (Kroncke et al. 2019).

Reported Carrier Data

PubMed ID Year Carriers Unaffected LQT3 BrS1 Other Other Disease
24687331 2014 1 1 0 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 1 0 -
VARIANT FEATURES ALONE: - 15 13 1 1 - -
Summary totals might not agree with the literature table because of duplicate patients, which were excluded from the total counts. We do not distinguish here between multiple missense codons. Missense variants are combined across degenerate codon substitutions since codon-level data were not consistently available for curation.

Functional Data

Peak and late/persistent current are relative to wildtype (100% being no different from wildtype). V0.5 act/inact are the voltages at which half of the maximal current is reached during an activation and inactivation protocol, each is in units of mV and relative to wildtype.
PubMed ID Year Cell Type Peak Current (%WT) V1/2 Act. (mV) V1/2 Inact. (mV) Late/Persistent Current (%WT)
24687331 2014

c.2436+12G>A has 57 previously observed neighbors within 15 angstroms

A residue within a folded protein on average has nearest neighbors that fall roughly into two shells: a "nearest" neighbor around 5-6 angstroms and a second shell around 11 angstroms. All variants shown in the rightmost column have been observed in at least one individual in the literature or gnomAD.

Neighbor Distance (Angstroms) Variants Observed in Individuals
811 8 R811G, R811H, c.2435_2436+3delTGGTAinsCGCCT,
808 12 R808H, R808P, R808C,
821 15
1351 11 M1351R, M1351V,
760 12 p.F760SfsX5,
780 13
1452 15
812 5 L812Q,
1350 12 I1350T, I1350L,
792 10
764 14 M764R, M764K,
791 8 L791F,
1344 13 F1344S, F1344L,
731 12 T731I,
806 12 V806M,
819 12
818 11
825 14
781 11 W781X,
1348 12 F1348L,
1349 14
788 6 I788V,
1346 13 L1346I, L1346P,
805 15 S805L,
782 14 N782T,
793 14 L793F,
728 15 V728I,
820 14
810 6
727 11
1456 15
734 11 M734V, c.2201dupT,
756 15
814 6 R814Q,
807 10
816 6 F816Y, F816L,
813 0 c.2437-5C>A, c.2436+12G>A,
757 13
786 11
1354 14
817 9 K817E,
809 7
815 7
790 11
1343 13
784 7 F784L,
796 15
785 9 D785N,
783 12 I783T,
730 12 N730K,
789 10 V789A, V789I,
753 14
1347 9
795 12
829 14
787 8
794 13